The Siege of Tenochtitlan, the capital of the Aztec Empire, came about in 1521 through the manipulation of local factions and divisions by Spanish conquistador Hernán Cortés. Though numerous battles were fought between the Aztecs and the Spanish army, which was composed of predominantly indigenous peoples, it was the siege of Tenochtitlan that was the final, decisive battle that led to the downfall of the Aztec civilization and marked the end of the first phase of the Spanish conquest of the Aztec Empire. The conquest of Mexico was part of the Spanish colonization of the Americas.